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Keywords: amino acid surfactants; surface active properties; environmental impactChemical warfare agents are a real threat to the security of mankind and efforts are constantly being made to counteract their effects by developing new formulations and technologies [1,2]. At the same time, there is a need to reduce the environmental impact of decontamination formulations. In surfactant-based decontamination formulations which include reactive compounds, the role of surfactants is to solubilize the sparingly soluble chemical warfare agents and catalyze their decontamination. In this work, we studied the stability in oxidizing agents and also in hard water, saline solutions and seawater formulations which contain amino acid surfactants [3], such as sodium lauroyl sarcosinate surfactant with low environmental impact made from renewable feedstock. The stability of formulations containing hydrogen peroxide was evaluated by the proportion of active oxygen remaining after variable lengths of time. The foamability and foam stability were assessed using the Ross-Miles method. The influence of water hardness and water salinity on the surface properties of surfactants were investigated by surface tension measurements performed on a KSV tensiometer Sigma 700 model, using the Du Nouy ring method. This study helps to expand the range of environmentally friendly surfactants that can be used in decontamination formulations of chemical warfare agents in land or maritime applications.

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Abstract. Autonomous underwater vehicle (AUV) a.k.a. underwater drones are subsea vehicles which operate in the underwater environment independently of direct human input. There is a growing interest in underwater data collection by using autonomous underwater vehicles within the oceanographic research community. In this paper, the Iver 2 AUV is examined to accomplish accurate side-scan data while executing well planned missions. Therefore, this papers goal is to establish the optimal use conditions for the AUV that RCN has so that we maximize the detection probability of sea bottom objects that can be risk factors and at the same time to cover a surface as large as possible during a single mission. IntroductionThe capability of protecting marine areas and important objectives situated near the shore against dangers associated with surface or underwater threats is critical for providing security in marine activities. Significant categories of threats are ships, small crafts and divers -these can either transport terrorists or various dangerous substances and materials in the protected area or can deposit such items on the sea bottom in the area, or can even conduct terrorist action themselves. This is the reason that the mission profile for a SIROLC-type system (System for detection, localization, tracking and identification of risk factors addressing important strategic objectives in littoral areas) should focus on two main objectives. The first one is to detect, locate and identify, through regular inspections and post-mission analysis the presence on the sea bottom or near it of objects that can become dangerous to the shipping activities in the area and for the protected objective.For this purpose SIROLC will have in its configuration an AUV-type subsystem for underwater surveillance [1] and which is fitted with specific sensors for orientation and determination of its own position and for determining the conductivity and salinity parameters, needed for calculating the sound speed profile at depth (information needed for increasing the performance of sonar systems). For observing the objects situated on the sea bottom the AUV subsystem is fitted with a high resolution side scanning sonar.A second objective is that of signaling the presence near the protected area of small ships or divers. There are various systems that can detect and track targets that move on surface or underwater, the most often used being of the active type (sonar and radar) [1].The AUV has a main role in the missions of detection, localization, tracking and identification of risk factors situated on the sea bottom as it can be deployed in relatively large areas with a high coverage degree with spatial and temporal resolutions that can not be achieved through other means. At the same time, the AUV efficiency is very high when compared to the costs and duration of measurements [3].

A plume model is used to describe the variation of the salt concentration at the discharge of a river into a saline water. The integral model of the plume behavior consists of a set of ordinary differential equations derived from conservation of mass, momentum and salt concentration. The temperatures of the plume and ambient saline water are considered equal. The concentration of the salt in the river water is null. The saline water is assumed motionless. After release from the river, the concentration of the salt in the plume increases by mixing with the ambient saline water. The rate of mixing depends upon the local plume and ambient fluid properties such as velocity and salt concentration.